Detective Sergeant Bruce Robertson (James McAvoy) wants a promotion. He is clearly the best man for the job, the rest of his colleagues are just idiots. Annoyingly, there's been a murder and Bruce's boss wants results. No problem for Bruce. He's in control, and when he solves the case and wins the promotion, his wife will return to him. No problem. But is life that simple? Is Bruce the man he really thinks he is? The tragic, hilarious and memorable answers unfold in Filth, a Jon S. Baird film based on the acclaimed novel by Irvine Welsh (Trainspotting).